Vershinina Svetlana D. RussiaYekaterinburgInstitute of Plant and Animal Ecology, Ural Branch of the Russian Academy of Sciences, 202 8 Marta St., Yekaterinburg 620144, Russias_verchok@list.ru Author's articles Influence of the geochemical background of the Western Caspian region of Azerbaijan on acid-base balance regulation of Pelophylax ridibundus (Pallas, 1771) (Amphibia, Ranidae) blood